Association of vitamin D status at birth and respiratory outcomes in preterm infants

Association Between Vitamin D Level and Neonatal Respiratory Distress Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

In recent years, vitamin D in the occurrence of lung diseases has gradually become a hot topic. Although the role of vitamin D in normal lung development has been confirmed, the correlation between vitamin D level and neonatal respiratory distress syndrome (NRDS) is not clear.

OBJECTIVE

To evaluate the association between vitamin D level and NRDS.

METHODS

We performed a comprehensive search of the following electronic databases: PubMed, Embase, Cochrane Library, Web of Science, and China National Knowledge Infrastructure (CNKI). Literature screening and quality assessment were performed according to inclusion and exclusion criteria. The Newcastle-Ottawa Scale was used to assess the methodological components of each study, and Stata 15.1 software to perform the Meta-analysis.

RESULTS

A total of nine case-control studies were included, with 653 infants with NRDS and 501 infants without NRDS. The Meta-analysis showed no heterogeneity across all studies(I²=0.0%, P=0.583). The fixed-effect model showed that 25 hydroxy vitamin D level of children in the NRDS group was significantly lower than that of the non-NRDS group(SMD = -0.51, 95%CI: -0.63 to -0.39, p ≤ 0.05).

CONCLUSION

This systematic review and meta-analysis study suggests that vitamin D deficiency is very likely to be a high-risk factor of NRDS, and reasonable vitamin D supplementation during pregnancy and after birth is of great significance.

Single nucleotide vitamin D receptor polymorphisms (FokI, BsmI, ApaI, and TaqI) in the pathogenesis of prematurity complications

The vitamin D receptor (VDR), coded by the VDR gene, plays a pivotal role in executing cellular functions when bound by the active form of vitamin D. Gene polymorphisms in this receptor have been increasingly associated with a heightened state of vulnerability to certain diseases. However, limited data is available concerning the role of VDR gene polymorphisms in preterm infant complications. In 114 premature infants (< 32 weeks gestation) we analyze four single nucleotide VDR polymorphisms (rs2228570 (FokI), rs1544410 (BsmI), rs797532 (ApaI), rs731236 (TaqI)) for their association with respiratory distress syndrome (RDS), intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC) and retinopathy of prematurity (ROP). The results show that BPD was almost four times more likely in infants with the genotype CC of ApaI (rs7975232) (OR 3.845; p = 0.038). While both BPD and NEC were 2.1 times more likely to occur in preterm infants with the allele C of ApaI (rs7975232) (respectively: OR 2.111 and OR 2.129, p < 0.05). The ApaI VDR polymorphism appears to influence incidence of BPD and NEC in preterm infants. Considering VDR polymorphisms in future genetic investigations, in preterm complications, may prove clinically relevant.